Removed primitive boolean getter and replaced with Boolean getter

Author: joviegas

services-custom/dynamodb-enhanced/src/main/java/software/amazon/awssdk/enhanced/dynamodb/document/EnhancedDocument.java

@@ -281,15 +281,18 @@ static Builder builder() {
     String getJson(String attributeName);
 
     /**
-     * Gets the boolean value for the specified attribute.
+     * Gets the {@link Boolean} value for the specified attribute.
      *
      * @param attributeName Name of the attribute.
-     * @return value of the specified attribute in the current document as a non-null Boolean.
+     * @return value of the specified attribute in the current document as a Boolean representation; or null if the attribute
+     * either doesn't exist or the attribute value is null.
      * @throws RuntimeException
-     *             if either the attribute doesn't exist or if the attribute
-     *             value cannot be converted into a boolean value.
+     *             if the attribute value cannot be converted to a Boolean representation.
+     *             Note that the Boolean representation of 0 and 1 in Numbers and "0" and "1" in Strings is false and true,
+     *             respectively.
+     *
      */
-    boolean getBoolean(String attributeName);
+    Boolean getBoolean(String attributeName);
 
 
     /**

services-custom/dynamodb-enhanced/src/main/java/software/amazon/awssdk/enhanced/dynamodb/internal/document/DefaultEnhancedDocument.java

@@ -189,11 +189,10 @@ public String getJson(String attributeName) {
     }
 
     @Override
-    public boolean getBoolean(String attributeName) {
+    public Boolean getBoolean(String attributeName) {
         Boolean value = get(attributeName, Boolean.class);
         if (value == null) {
-            throw new IllegalStateException("Value of " + "attribute " + attributeName + " of type null cannot be converted"
-                                            + " into a boolean value");
+            return null;
         }
         return value.booleanValue();
     }

services-custom/dynamodb-enhanced/src/test/java/software/amazon/awssdk/enhanced/dynamodb/document/EnhancedDocumentTest.java

@@ -407,9 +407,7 @@ void accessingNulAttributeValue() {
 
         Assertions.assertNull(enhancedDocument.getString(NULL_KEY));
         Assertions.assertNull(enhancedDocument.getList(NULL_KEY, EnhancedType.of(String.class)));
-        assertThatIllegalStateException().isThrownBy(() -> enhancedDocument.getBoolean(NULL_KEY))
-                                         .withMessage("Value of attribute nullKey of type null cannot be converted into a "
-                                                      + "boolean value");
+        assertThat(enhancedDocument.getBoolean(NULL_KEY)).isNull();
 
     }